Cross reference
Leviticus 15:6
6 And he that sitteth on anything whereon he that hath the issue sat shall wash his clothes, and bathe himself in water, and be unclean until the even.
Isaiah 1:16
16 Wash you, make you clean; put away the evil of your doings from before mine eyes; cease to do evil;
James 4:8
8 Draw nigh to God, and he will draw nigh to you. Cleanse your hands, ye sinners; and purify your hearts, ye doubleminded.